不同钾肥配施对烤烟质体色素和碳氮代谢及品质的影响

为探究不同钾肥配施对烤烟碳氮代谢和品质的影响，采用田间试验研究了不同钾肥及其配施对烤烟质体色素、部分碳氮代谢关键酶活性、常规化学成分和中性致香物质的影响。结果表明，与施用普通钾肥（对照）相比，缓释钾肥处理提高了烟株各生育期的氮代谢和成熟期的碳代谢。缓释钾肥＋普通钾肥处理和缓释钾肥＋普通钾肥＋黄腐酸钾处理对烟叶质体色素含量和碳氮代谢水平的提高作用比较明显，而缓释钾肥＋普通钾肥处理在烟株生育后期仍然有很高的叶绿素含量与硝酸还原酶活性，阻碍了烟叶碳氮代谢的适时转化和烟株正常落黄成熟。缓释钾肥＋普通钾肥＋黄腐酸钾处理不但能提高烟叶生育前期质体色素含量和碳氮代谢水平，而且能够促进烟叶质体色素适时降解和碳氮代谢的协调。总体来看，缓释钾肥及与其他钾肥的配施显著提高了烤后烟叶中的钾含量，提高了钾氯比和两糖比，使烟叶化学成分更趋于协调，同时提高了大多数种类的香气物质含量，此外，缓释钾肥＋普通钾肥＋黄腐酸钾处理还提高了新植二烯和香气物质总量。综合来看，缓释钾肥＋普通钾肥＋黄腐酸钾处理最有利于优质烟叶的形成。

Effects of Combining Application of Various Potassium Fertilizers on Plastid Pigment,Carbon-Nitrogen Metabolism and Quality in Flue-cured Tobacco

A field experiment was conducted to investigate the effect of combining application of various potassium （K） fertilizers on plastid pigment, some enzyme activities in carbon-nitrogen metabolism and quality in flue-cured tobacco （cv. zhongyan 100 ）. The results showed that, compared to common K fertilizer, slow release K fertilizer improved the carbon metabolism in all growth stages of flue-cured tobacco and the nitrogen metabolism in maturity stage, common K fertilizer ＋ slow release K fertilizer treatment and common K fertilizer ＋ slow release K fertilizer ＋ fulvic acid K treatment improved the contents of plastid pigment and the level of carbon-nitrogen metabolism. However, the contents of chl and activity of nitrate reductase in flue-cured tobacco leaves with treatment of common K fertilizer ＋ slow release K fertilizer was still high in maturity stage, which impeded the nitrogen metabolism transform into carbon metabolism timely and the tobacco leaves mature normally. The treatment common K fertilizer ＋ slow release K fertilizer ＋ fulvic acid K not only improved the contents of plastid pigment and the level of carbon-nitrogen metabolism in early growth stages of flue-cured tobacco leaves, but also promoted the nitrogen metabolism transform into carbon metabolism timely and the tobacco leaves mature normally. Overall, the slow release K fertilizer and the combined application of other K fertilizer significantly improved the potassium content, ratio of potassium to chlorine and ratio of reducing sugar to total sugar in cured tobacco leaves. The chemical composition in cured tobacco leaves tended to be more harmonious, while total aroma constituents except neophytadiene and many different kinds of aroma constituents increased. Besides, the neophytadiene and total aroma constituents in the treatment with common K fertilizer ＋ slow release K fertilizer ＋ fulvic acid K also improved. Therefore this treatment was proposed as the best treatment for high quality tobacco leaves.